Despite an improved outlook, quality of life issues remain crucial for patients with HIV/AIDS. In two recent AHCPR-funded studies, we showed that: 1) patients with HIV/AIDS have a powerful will to live as manifested by very high time-tradeoff utilities (health values); 2) half of patients felt that their life is better now than before they had HIV infection; and 3) spirituality was an independent predictor of health values and a sense that life has improved. Our findings regarding spirituality were limited by the fact that we asked a single spirituality question at a single site at a single point in the HIV/AIDS epidemic. Spirituality/religion is a complex construct involving a sense of meaning and purpose to life, faith, religiosity, and other concepts. Whether the will to live is rife among other patients with HIV/AIDS; whether spirituality exerts a salutary effect across all racial and ethnic groups, and if so, by what mechanism(s); and whether spirituality leads to a will to live or vice versa are unknown. Thus, to build on our previous findings, we propose a 4-year longitudinal study with two aims: (1) using more detailed questionnaires and adding a second study site to ensure patient diversity, to characterize and assess the extent of spirituality in patients with HIV/AIDS; (2) using a new conceptual model founded on previous work by the investigators, to determine the relationship of spirituality and health-related quality of life to the will to live and to whether patients feel that life has improved, and to assess potential mechanisms by which spirituality/religion may influence (positively or negatively) one's will to live or feeling that life has improved. We plan to interview 325-350 patients with various stages of HIV/AIDS from Cincinnati and Washington, D.C. Patients will be interviewed at two points in time separated by 12-15 months. The questionnaire battery will include the health rating scale, time tradeoff, and standard gamble; a question comparing life now with life before (being aware of) being infected with HIV; the HIV/AIDS-Targeted Quality of Life instrument; the CESD-10 depression scale; three measures of spirituality, religion, and religious coping; five pilot items addressing attitudes of organized religion towards HIV/AIDS; and four scales selected to address various mediating mechanisms by which spirituality/religion might operate. We anticipate that such information will be of great benefit to patients with HIV/AIDS in their quest to make the best of a potentially devastating illness.